The GOGREEN survey: transition galaxies and the evolution of environmental quenching

ABSTRACT We measure the rate of environmentally driven star formation quenching in galaxies at z ∼ 1, using eleven massive ($M\approx 2\times 10^{14}\, \mathrm{M}_\odot$) galaxy clusters spanning a redshift range 1.0 < z < 1.4 from the GOGREEN sample. We identify three different types of transition galaxies: ‘green valley’ (GV) galaxies identified from their rest-frame (NUV − V) and (V − J) colours; ‘blue quiescent’ (BQ) galaxies, found at the blue end of the quiescent sequence in (U − V) and (V − J) colour; and spectroscopic post-starburst (PSB) galaxies. We measure the abundance of these galaxies as a function of stellar mass and environment. For high-stellar mass galaxies (log M/M⊙ > 10.5) we do not find any significant excess of transition galaxies in clusters, relative to a comparison field sample at the same redshift. It is likely that such galaxies were quenched prior to their accretion in the cluster, in group, filament, or protocluster environments. For lower stellar mass galaxies (9.5 < log M/M⊙ < 10.5) there is a small but significant excess of transition galaxies in clusters, accounting for an additional ∼5–10 per cent of the population compared with the field. We show that our data are consistent with a scenario in which 20–30 per cent of low-mass, star-forming galaxies in clusters are environmentally quenched every Gyr, and that this rate slowly declines from z = 1 to z = 0. While environmental quenching of these galaxies may include a long delay time during which star formation declines slowly, in most cases this must end with a rapid (τ < 1 Gyr) decline in star formation rate.

LoRa-Based Traffic Flow Detection for Smart-Road

This paper presents a wireless traffic flow detection system, mainly focused on conditions in which the traffic flow is slow or stopped, which increases the risk of highway accidents. To achieve this goal, a Low Power Wide Area Network (LPWAN) based on LoRa called Short LoRa has been developed. This LoRa sub-network complies with the European Telecommunications Standards Institute (ETSI) harmonized standard for its compatibility in Europe countries. In addition, the development of the devices has allowed them to also work on a LoRaWAN network. The introduced development has been compared to a reference system mounted with laser barriers that provided a high accurate comparison. Field tests of the system have been carried out and the data obtained in the measurement has been analyzed with two different methods, and both of them were valid for the application. The results can determine vehicle speed with adequate precision at low speeds. The attenuating behavior of the communication signal is also analyzed through the Radio Signal Strength Indicator (RSSI). The relationship between vehicle speed, gate distances and RSSI attenuation has been studied. The system is proven to have efficient results in detecting traffic flow under the conditions for which it has been developed.

«ATYPICAL» PROBLEMS OF URBANISM CLASSIFICATION, CHARACTERISTICS AND APPROACHES TO THE SOLUTION

In the urban sphere, the problems become more complicated and there are many violations and errors, so the problem of streamlining the problems of urban planning and substantiation of new methodological tools for solving «atypical» problems is relevant, as classical methods are ineffective. In the article the author solved problems: classification, specification of structure and maintenance of urban problems; substantiation of typological features and selection of «atypical» urban problems; outlining the general algorithm and methods of their solution; checks of orderly methodical tools on urban tasks of Lviv. Existing methods and solutions of urban problems are systematized. The general scientific methods of research include: theoretical (convergence from the abstract to the concrete, the method of formalization, the historical method, the system-structural, the method of studying documents); empirical (method of observation, comparison, field surveys, measurements) and empirical-theoretical (abstraction, analysis, synthesis, logical method, modeling), as well as statistical, historical, sociological and cartographic analysis. The classification and «atypical» problems of urban planning are carried out, the methodical tools of their solution are arranged. Methods and means to increase the efficiency of functioning and development of urban systems are based on the provisions of fuzzy sets and their essence. Thus, the new methods should classify urban problems by input and output indicators and knowledge of the internal structure of the system (processes and behavior). According to the theory of validity, in the first step, data are collected using various methods, denoted by codes, grouped into groups to make them more effective. Classification and characterization of «atypical» tasks, as well as updated methodological tools were tested on the example of Lviv — the principles and ways of reforming and developing its spatial structure. The forecast of the future is based on the genesis and historical ways of development of territories and cities. New ways or elimination of old ones meet at radical reforms, and development is caused not only by historical longevity and change of conditions, but also by new processes and behavior of system. There are ways to solve «atypical» problems: simple, including one direction; more complex covers the main direction and two or three additional subdirections; complex includes one or two main directions and several subdirections. This substantiates the feasibility of permanent city design and updating of urban planning documentation.

Toronto Water Vapor Lidar Inter-Comparison Campaign

This study presents comparisons between vertical water vapor profile measurements from a Raman lidar and a new pre-production broadband differential absorption lidar (DIAL). Vaisala’s novel DIAL system operates autonomously outdoors and measures the vertical profile of water vapor within the boundary layer 24 h a day during all weather conditions. Eight nights of measurements in June and July 2018 were used for the Toronto water vapor lidar inter-comparison field campaign. Both lidars provided reliable atmospheric backscatter and water vapor profile measurements. Comparisons were performed during night-time observations only, when the York Raman lidar could measure the water vapor profile. The purpose was to validate the water vapor profile measurements retrieved by the new DIAL system. The results indicate good agreement between the two lidars, with a mean difference (DIAL–Raman) of 0.17 ± 0.14 g/kg. There were two main causes for differences in their measurements: horizontal displacement between the two lidar sites (3.2 km) and vertical gradients in the water vapor profile. A case study analyzed during the campaign demonstrates the ability for both lidars to measure sudden changes and large gradients in the water vapor’s vertical structure due to a passing frontal system. These results provide an initial validation of the DIAL’s measurements and its ability to be implemented as part of an operational program.

THE INFLUENCE OF PAVEMENT–VEHICLE INTERACTION ON HIGHWAY FUEL CONSUMPTION BY FIELD MEASUREMENT

Field experiments are performed in which Fuel Consumptions (FCs) are measured by operating passenger car over thirteen one-mile roadway sections at two highway speeds in Florida. The sections are composed of 6 flexible pavement sections and seven rigid pavement sections with varied pavement surface conditions and testing temperature. The first objective is to capture the fuel differences between flexible pavement and rigid pavement considering the effect of pavement roughness and pavement temperature. By ANalysis of COVAriance (ANCOVA), results show less fuel is consumed on rigid pavement opposed to flexible pavement by 2.25% at 93 km/h and 2.22% at 112 km/h. Fuel differences are found statistically significant at 95% Confidence Level (C.L.). Fuel savings on rigid pavement exhibits good agreement with authors’ Phase I direct comparison field study. Furthermore, fuel data from flexible pavement is applied to calibrate the Highway Development and Management IV (HDM-4) FC model in order to detect and quantify the impact of pavement deflection on FC. Calibrated models are evaluated and validated with experiment data. By results, the deflection-indhuced fuel effect is disclosed by the positive deflection adjustment coefficient generated from the calibration. It is also found that an increase of 0.1mm in pavement deflection at 25 °C (pavement temperature) would increase the FC by 1.53% at 93 km/h and 1.46% at 112 km/h. Results demonstrate good agreement with other findings.

Evaluating the performance of commonly used gas analysers for methane eddy covariance flux measurements: the InGOS inter-comparison field experiment

The performance of eight fast-response methane (CH4) gas analysers suitable for eddy covariance flux measurements were tested at a grassland site near the Cabauw tall tower (Netherlands) during June 2012. The instruments were positioned close to each other in order to minimise the effect of varying turbulent conditions. The moderate CH4 fluxes observed at the location, of the order of 25 nmol m−2 s−1, provided a suitable signal for testing the instruments' performance. Generally, all analysers tested were able to quantify the concentration fluctuations at the frequency range relevant for turbulent exchange and were able to deliver high-quality data. The tested cavity ringdown spectrometer (CRDS) instruments from Picarro, models G2311-f and G1301-f, were superior to other CH4 analysers with respect to instrumental noise. As an open-path instrument susceptible to the effects of rain, the LI-COR LI-7700 achieved lower data coverage and also required larger density corrections; however, the system is especially useful for remote sites that are restricted in power availability. In this study the open-path LI-7700 results were compromised due to a data acquisition problem in our data-logging setup. Some of the older closed-path analysers tested do not measure H2O concentrations alongside CH4 (i.e. FMA1 and DLT-100 by Los Gatos Research) and this complicates data processing since the required corrections for dilution and spectroscopic interactions have to be based on external information. To overcome this issue, we used H2O mole fractions measured by other gas analysers, adjusted them with different methods and then applied them to correct the CH4 fluxes. Following this procedure we estimated a bias of the order of 0.1 g (CH4) m−2 (8% of the measured mean flux) in the processed and corrected CH4 fluxes on a monthly scale due to missing H2O concentration measurements. Finally, cumulative CH4 fluxes over 14 days from three closed-path gas analysers, G2311-f (Picarro Inc.), FGGA (Los Gatos Research) and FMA2 (Los Gatos Research), which were measuring H2O concentrations in addition to CH4, agreed within 3% (355–367 mg (CH4) m−2) and were not clearly different from each other, whereas the other instruments derived total fluxes which showed small but distinct differences (±10%, 330–399 mg (CH4) m−2).

Evaluating the performance of commonly used gas analysers for methane eddy covariance flux measurements: the InGOS inter-comparison field experiment

The performance of eight fast-response methane (CH4) gas analysers suitable for eddy covariance flux measurements were tested at a grassland site near the Cabauw tall tower (Netherlands) during June 2012. The instruments were positioned close to each other in order to minimize the effect of varying turbulent conditions. The moderate CH4 fluxes observed at the location, of the order of 25 nmol m−2 s−1, provided a suitable signal for testing the instruments' performance. Generally, all analysers tested were able to quantify the concentration fluctuations at the frequency range relevant for turbulent exchange and were able to deliver high-quality data. The tested cavity ring-down spectrometer (CRDS) instruments from Picarro, models G2311-f and G1301-f, were superior to other CH4 analysers with respect to instrumental noise. As an open-path instrument susceptible to the effects of rain, the LI-COR LI-7700 achieved lower data coverage and also required larger density corrections; however, the system is especially useful for remote sites that are restricted in power availability. In this study the open-path LI-7700 results were compromised due to a data acquisition problem in our data-logging setup. Some of the older closed-path analysers tested do not measure H2O vapour concentrations alongside CH4 (i.e. FMA1 and DLT-100 by Los Gatos Research) and this complicates data processing since the required corrections for dilution and spectroscopic interactions have to be based on external information. To overcome this issue, we used H2O mole fractions measured by other gas analysers, adjusted them with different methods and then applied them to correct the CH4 fluxes. Following this procedure we estimated a bias on the order of 0.1 g (CH4) m−2 (8% of the measured mean flux) in the processed and corrected CH4 fluxes on a monthly scale due to missing H2O concentration measurements. Finally, cumulative CH4 fluxes over 14 days from three closed-path gas analysers, G2311-f (Picarro Inc.), FGGA (Los Gatos Research) and FMA2 (Los Gatos Research), which were measuring H2O vapour concentrations in addition to CH4, agreed within 3% (355–367 mg (CH4) m−2) and were not clearly different from each other, whereas the other instruments derived total fluxes which showed small but distinct differences (±10%, 330–399 mg (CH4) m−2).

The Method for Object-Based Diagnostic Evaluation (MODE) Applied to Numerical Forecasts from the 2005 NSSL/SPC Spring Program

The authors use a procedure called the method for object-based diagnostic evaluation, commonly referred to as MODE, to compare forecasts made from two models representing separate cores of the Weather Research and Forecasting (WRF) model during the 2005 National Severe Storms Laboratory and Storm Prediction Center Spring Program. Both models, the Advanced Research WRF (ARW) and the Nonhydrostatic Mesoscale Model (NMM), were run without a traditional cumulus parameterization scheme on horizontal grid lengths of 4 km (ARW) and 4.5 km (NMM). MODE was used to evaluate 1-h rainfall accumulation from 24-h forecasts valid at 0000 UTC on 32 days between 24 April and 4 June 2005. The primary variable used for evaluation was a “total interest” derived from a fuzzy-logic algorithm that compared several attributes of forecast and observed rain features such as separation distance and spatial orientation. The maximum value of the total interest obtained by comparing an object in one field with all objects in the comparison field was retained as the quality of matching for that object. The median of the distribution of all such maximum-interest values was selected as a metric of the overall forecast quality. Results from the 32 cases suggest that, overall, the configuration of the ARW model used during the 2005 Spring Program performed slightly better than the configuration of the NMM model. The primary manifestation of the differing levels of performance was fewer false alarms, forecast rain areas with no observed counterpart, in the ARW. However, it was noted that the performance varied considerably from day to day, with most days featuring indistinguishable performance. Thus, a small number of poor NMM forecasts produced the overall difference between the two models.